Furnace construction



D60 6,- 1938- G'. w. DAvf-:Y 2,139,004 l FURNACE CONSTRUCTION y Filedr July 28, 1937 2 Sheets-Shea?.` 1

f SM@ @01265 Wl 3m/EY Dec. 6, 1938. G. w. DAVEY FURNAGE coNsTHUcTIoN Filed July 28, 1957 .2 sheetsfsheet z 'GEORGE' W DAVE? u www Patented Dec. 6, 1938 UNITED STATES PATENT OFFICE 9 Claims.

This invention relates to furnace construction, and more particularly to the construction of water tube boiler baffles, water cooled arches, water cooled walls, and the like.

Constructions of this type often comprise a series of spaced parallel water tubes forming a supporting structure, and blocks of refractory material mounted on the water tubes to close the spaces between the tubes. With some prior ,constructions the blocks are not firmly secured to the tubes, and may become dislodged therefrom by sudden increases in the furnace pressure. Other constructions are expensive to manufacture and difficult to install. Still others fail to remain tight in service, and thus allow the furnace gases to leak through between the blocks. In still other constructions the water tubes are considerably exposed, and the furnace temperature is lowered to an undesirable extent by the 'resultant absorption of radiant heat.

It is accordingly one object of the invention.

to provide a furnace construction comprising spaced water tubes and refractory blocks firmly secured to the tubes to close the spaces therebetween. It is a further object of the invention to provide a furnace construction comprising spaced water tubes and refractory blocks mounted thereon, which will be comparatively simple and inexpensive to manufacture and install.

It is a further object of the invention to provide a furnace construction which willremain substantially gas tight throughout a long life of servlce.

It is a further object of the invention to provide a furnace construction comprising spaced water tubes and refractory .blocks mounted thereon, the blocks covering the tubes completely to prevent excessive lowering of the furnace temperature.

With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.

In accordance with my invention in its preferred form, I provide a series of spaced parallel water tubes with their axes in a common plane. These water tubes serve as a supporting structure for blocks of refractory material which may be arranged in rows extending transversely yof the tube axes. Each block comprises a main body portion. located directly between the tubes, and two laterally projecting portions forming the inner and outer faces of the block. These laterally projecting portions have a length substantially equal to the distance between the axes `of adjacent tubes, so that the blocks in each row are in contact with each other and are thereby locked in position. At least one of the laterally projecting portions on each block is .offset laterally from the body porti-on in order that the block may be inserted between two tubes', swung about `the axis of one of the tubes, and then moved along the tubes into its place in the row. Preferably the laterally projecting portions overlap the main body portions of the adjacent blocks. The blocks in adjacent rows are oppositely positioned in order to break the joints and provide a strong bond. The main body portions of the blocks in adjacent rows preferably overlap, with ship-lap or tongue and groove joints, to form a tight seal.

Referring to the drawings illustrating one embodiment of the invention, and in which like. reference numerals indicate like parts,

Fig. 1 is an elevation of a furnace structure;

Fig. 2 is a section on the line 2 2 of Fig. 1;

Fig. 3 is Va section on the line 3 3 of Fig. l, with one block displaced to show the manner in `which the blocks are assembled;

Fig. 4 is a section on the line 4 4 of Fig. 1;

Fig. 5 is a perspective view of one of the blocks;

Fig. 6 is an elevation of a modified furnace structure;

Fig. '7 is .a section on the line 1 1 of Fig. 6;

Fig. 8 is a section on the line 8 8 of Fig. 6, with one block displaced to show the manner in which the blocks are assembled;

Fig. 9 is a section on the line 9 9 of Fig. 6; and

Fig. 10 is a perspective View of one of the" blocks.

The embodiment illustrated in Figs 1 to 5 comprises a series of spaced parallel water tubes I5 with their axes located in a common plane. These tubes are shown connected at one end to a header or drum I6. It Will be understood that these tubes may form part of a steam boiler, water wall, or water cooled furnace arch, and

that any suitable provision may be made for the` maintenance of water circulation therethrough.

The Water tubes l5 form a supporting structure for a plurality of refractory blocks Il arranged in rows extending transversely of the tube axes. Each block comprises a main body portion I9, and twolaterally projecting portions forming the inner and outer faces of the block. These portions 20 are substantially equal in length to the distance between the axes of vadjacent tubes l5, and the parts are so constructed and ar-y ranged that at assembly the portions I9 of the blocks will substantially fill the spaces between the tubes and the corresponding portions 2li of adjacent blocks in the same row will be in contact, so that the blocks are locked in position. In order that the parts may be assembled, at least one of the laterally projecting portions 20 of each block is offset laterally from the body portion I 9. As shown in Fig. 3, this makes it pos'- sible to insert this offset portion 20 between the water tubes and then swing the block inwardly about the axis of one of the tubes, whereupon the block can be slid axially along the tubes into its proper place in the row. Preferably both of the portions 29 are offset so that the block can be inserted fr-om either side, and in this particular embodiment they are offset in opposite directions, thus forming a Z-shaped block. Preferably the portions 28 are offset from the main body portions I9 sufficiently to form notches or recesses 2| into which the ends of the portions 20 of adjacent blocks extend at assembly in overlapping relation to the portions I9.

It will be noted from a comparison of Figs. 3 and 4 that the blocks in adjacent rows are oppositely positioned. In other words, the blocks in adjacent rows are so placed that the corresponding portions 2l) are offset in opposite directions. As a result of this construction the vertical joints are broken, as shown in Fig. 1, and a strong bond is provided.

In order to minimize gas leakage through the structure, the main body portions IS in adjacent rows are arranged to overlap. This may be accomplished by oifsetting the inner and outer halves of each block in a direction parallel to the axes of the tubes thereby providing ship-lap joints 23 as shown in Fig. 2. It will be noted that only one shape of block is required in spite of the reversal of the blocks in adjacent rows.

In Figs. 6 to 10 there is illustrated a slightly modied construction comprising a series of spaced parallel water tubes 25 with their axes in a common plane, these tubes being connected at one end to a header or drum 26. The tubes 25 form a supporting structure for a plurality of refractory blocks 2 arranged in rows extending transversely of the tube axes. Each block comprises a main body portion 29, and two laterally projecting portions 30 forming the inner and outer faces of the block. These portions 30 are substantially equal in length to the distance between the axes of adjacent tubes 25, and the parts are so constructed and arranged that at assembly the portions 29 of the blocks will substantially fill the spaces between the tubes, and the corresponding portions 30 of adjacent blocks will be in contact, so that the blocks are locked in position. -In order that the parts may be assembled, at least one of the laterally projecting portions 30 of each block is offset laterally from the body portion 29. As shown in Fig. 8, this makes it possible to insert this offset portion 30 between the water tubes and then swing the block inwardly about the axis of one of the tubes, whereupon the block can be slid axially along the tubes into its proper place in the row. Preferably both of the portions 30 are oiset, and in this particular embodiment they are offset in the same direction, thus forming a U-shaped block. Preferably the portions 3B are oiset from the main body portions 29 sufciently to form notches or recesses 3i into which the ends of the portions 3i] of adjacent blocks eX- tend at assembly in overlapping relation to the portions 29.

It will be noted from a comparison of Figs. 8 and 9 that the blocks in adjacent rows are oppositely positioned. In other words, the blocks in adjacent rows are so placed that the portions 30 are offset in opposite directions. As a result of this construction the vertical joints are broken, as shown in Fig. 6, and a strong bond is provided.

In order to minimize gas leakage through the structure, the main body portions 29 in adjacent rows are arranged to overlap. This may be accomplished by providing a groove 33 (Fig. '7) in one end of the portion 29, and a rib or tongue 34 in the other end of the portion 29. At assembly the tongues 34 t within the grooves 33. It will be noted that only one shape of block is required in spite of the reversal of the blocks in adjacent rows.

With either of the modcations illustrated, the blocks are securely locked to the tubes and cannot be accidentally displaced, yet they can be readily inserted and removed. The structures are substantially gas tight and will remain so during a long life of service. The tubes are completely covered by the blocks, so that there will be no undue lowering of the furnace temperature. The tubes can be placed in any desired position, and they may be vertical, horizontal or inclined.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. Furnace construction comprising a series of spaced parallel water tubes, and refractory blocks mounted on the water tubes, each block having a l main body portion which substantially lls the space between two adjacent tubes, and two laterally projecting portions forming the inner and outer faces of the block, one vof said projecting portions of each block being substantially in contact with the corresponding projecting portion of the laterally adjacent block, and one ofsaid projecting portions on each block being offset laterally from the main body portion suiliciently to jecting portions of adjacent blocks in the same row being substantially in contact, and one of said projecting portions on each block being olfset laterally from the main body portion sufficiently to allow the block to be inserted between the tubes and then swung about one of the tubes, whereupon it may be slid along the tubes into its proper position, the blocks in adjacent rows being voppositely positioned to provide broken joints.

3. Furnace construction comprising a series of spaced parallel water tubes, andrefractory blocks mounted on the water tubes, each block having a main body portion located between two adjacent tubes, and two laterally projecting portions Vforming the inner and outer faces of the block, the said projecting portions being substantially equal in length to the distance between the axes of the tubes, and one of said projecting portions on each block being offset laterally from the main body portion sufciently to allow the block to be inserted between the tubesand then swung about one of the tubes, whereupon it may be slid along the tubes into its proper position.

Al. Furnace construction comprising a series of spaced parallel water tubes, and refractory blocks mounted on the water tubesfeach block having a main body portion which substantially fills the space between two adjacent tubes, and two laterally projecting portions forming the inner and outer faces of the block, the corresponding projecting portions of laterally adjacent blocks being substantially in contact, and both of said project-ing portions on each block being offset laterally from the main body portion sufiiciently to allow the block to be inserted between the tubes from either side and then swung about one of the tubes, whereupon it may be slid along the tubes into its proper position.

5. Furnace construction comprising a series of spaced parallel water tubes, and refractory blocks mounted on the water tubes, each block having a main body portion located between two adjacent tubes, and two laterally projecting portions forming the inner and outer faces of the block, the said projecting portions of laterally adjacent blocks being substantially in Contact, and the two projecting portions on each block being offset laterally from the main body portion in opposite directions suiiiciently to form a Z-shaped block and to allow the block to be inserted between the tubes from either side and then swung about one of the tubes, whereupon it may be slid along the tubes into its proper position.

6. Furnace construction comprising a series of spaced parallel water tubes, and refractory blocks mounted on the water tubes, each block having a main body portion which substantially lls the space between two adjacent tubes, and two laterally projecting portions forming the inner and outer faces of t-he block, the corresponding projecting portions of laterally adjacent blocks being substantially in contact, and the two projecting portions on each block being oset laterally from the main body portion in the same direction sufficiently to form a U-shaped block and to allow the block to be inserted between the tubes from either side and then swung about one of the tubes,

whereupon it may be slid along the tubes into its proper position.

'7. Furnace construction comprising a series of spaced parallel water tubes, and refractory blocks mounted on the water tubes, each block having a main body portion located between twoadjacent tubes, and two laterally projecting portions forming the inner and outer faces of the block, the said projecting portions of laterally adjacent blocks being substantially in Contact, and both of said projecting portions on each block being offset laterally from the main body portion Sufficiently to provide notches into which the projecting portions of adjacent blocks extend in overlapping relation to the body portion and to allow the block to be inserted between the tubes from either side and then swung .about one of the tubes, whereupon it may be slid along the tubes into its proper position.

8. Furnace construction comprising a series of spaced parallel water tubes, and refractory blocks mounted on the water tubes in rows extending transversely of the tubes, each block having a main body portion which substantially lls the space between two adjacent tubes, and twolaterally projecting portions forming the inner and outer faces of the block, the corresponding projecting portions of adjacent blocks in the same row being substantially in contact, and one of said projecting portions on each block being offset laterally from the main body portion sufficiently to allow the block to be inserted between the tubes and then swung about one of the tubes, whereupon it may be slid along the tubes into its proper position, the main body portions of the blocks in adjacent rows being shaped to provide overlapping joints in order to minimize gas leakage through the structure.

9. A refractory block for a furnace construction comprising a main body portion and laterally projecting portions on opposite sides of the body portion, both of the projecting portions being oifset from the body portion suiciently to provide notches into which the projecting portions of adjacent blocks may extend at assembly in overlapping relation to the body portion.

GEORGE W. DAVEY. 

